Time to postoperative pulmonary complications, composite endpoint, and in-hospital mortality for patients ventilated with positive end–expiratory pressure at least 5 cm H₂O and tidal volume up to 7 ml/kg vs. 8 to 10 ml/kg vs. more than 10 ml/kg predicted body weight (PBW). Cox regression models adjusted for age, American Society of Anesthesiologists, and presence of risk factor for postoperative pulmonary complications. HR = hazard ratio.